Marine engines having outboard or inboard/outboard drive units typically include lower unit housings that house parts such as a propeller shaft, bearings, a bearing currier, seals and the like. The interior cavity of the housing within which such parts are positioned defines a reservoir for lubricant. Thus, when the reservoir is fully charged with a lubricant, the parts housed in the lower unit are immersed in the lubricant and their useful working life is thereby extended.
The lubricant specified for use in such engines is sold to consumers in ten ounce squeeze tubes having conical spouts with threads at the base thereof. To charge the lubricant into a lower unit, a vent near the engine housing is opened, and a drain plug at the bottom of the lower unit is removed; this allows the lubricant, also known as gear lube, to drain from the reservoir Next, the conical spout of the squeeze tube is cut, the spout is inserted into the uncapped drain opening, and the tube is squeezed.
It is important to note that engine manufacturer's require that the gear lube be charged into the lower unit reservoir from the bottom thereof, i.e., the gear lube must be introduced through the uncapped drain opening. If the drain plug is reinstalled after the old gear lube is drained from the reservoir, and the gear lube introduced into the vent opening vertically spaced thereabove, the outdrive gears can be damaged due to trapped air pockets and all engine warranties are voided.
Thus, the reservoir must be filled from the bottom thereof. Accordingly, after the first tube of gear lube has been introduced thereinto, the individual handling the lube-changing procedure must remove the conical spout of the squeeze tube from the drain opening and quickly cover the opening before the newly introduced gear lube can drain out. The spout of a second tube must then be cut off with a first hand while a second hand remains occupied with plugging the drain opening. The drain opening must then be uncovered and the spout of the second tube quickly inserted thereinto to again prevent unwanted draining of fresh gear lube. Since a typical lower unit reservoir holds the contents of about four tubes, this cumbersome procedure must be repeated until the reservoir is finally filled. The drain plug must be quickly reinstalled after the last tube has been emptied.
Unfortunately, it is not possible to fully empty a gear lube squeeze tube when the above-described procedure is followed, primarily because only one hand is available to perform the tube-squeezing function. The other hand must apply upward pressure to keep the tube seated in the drain opening. Experience has shown that two to four ounces of gear lube in each ten ounce tube is left within each tube because only one hand is available to squeeze it. Thus, a boat owner will waste the equivalent of one full tube for every four or five ten ounce squeeze tubes used.
Commercial marine engine maintenance operations do not employ the inefficient technique just described. Instead, the gear lube is pumped from a fifty-five gallon drum into the lower unit lubrication reservoir, thereby completely avoiding the use of individual squeeze tubes and the awkward and inefficient method of emptying them.
However, individual boat owners who prefer to do their own routine maintenance normally do not have access to fifty-five gallon drums of gear lube, nor do they typically own the pump and other equipment used by commercial operators.
Accordingly, a number of inventors have tried to develop devices that facilitate the use of squeeze tubes. For example, U.S. Pat. No. 3,955,648 to Walker discloses a fitting that replaces the drain plug supplied by the marine manufacturer, and the new fitting is specifically configured to facilitate the introduction of gear lube into the reservoir. However, most marine engine manufacturers will void their warranty if parts of the engine are replaced or modified. Moreover, the Walker fitting is not universal and has utility only in connection with drain openings of large diameters. Engine outdrives having small diameter drain openings, such as those manufactured by Nissan Corporation, cannot accept the Walker fitting
An apparatus having utility in high pressure systems is shown in U.S. Pat. No. 3,795,262 to Post.
Other U.S. patents of interest include U.S. Pat. No. 3,976,110 to White, U.S. Pat. No. 3,647,024 to Wick, U.S. Pat. No. 2,016,809 to Bystricky, U.S. Pat. No. 4,589,626 to Kurtz, U.S. Pat. No. 3,942,228 to Buckman, U.S. Pat. No. 2,995,214 to Sensui, and U.S. Pat. No. 3,307,598 to Lowenthal.